(Based on AI research) fossile fuel production takes a few years to recoup investment. Only refineries seem quite long term (15-20 years). I'm sure the companies have projections about future demand to decide which projects are worth pursuing. If they miscalculate, the oil companies loose money (oh no! /s). Anyway, you won't loose money on this.

There is of course also an argument about national security, not being at the whim of some Iranian dictator. So some form of government investment would be justified, but not necessary IMO.